Traffic-controlling system for railways.



A. V. T. DAY. TRAFFIC CONTROLLING SYSTEM FOR RAILWAYS.

APPLICATION FILED 0OT.29, 1908.

Patented Dec. 1

STATES PATENT ALBERT V. T. DAY, OF NEW ROCHELLE, NEW YORK, ASSIGNOR TO THE HALL SWITCH AND SIGNAL COMPANY, A CORPORATION OF MAINE.

TRAFFIC-CONTROLLING SYSTEM FOR RAILWAYS.

Application filed October 29, 1908.

To all whom it may concern:

Be it known that I, ALBERT V. T. DAY, a citizen of the United States, residing at New Rochelle, in the county of Westchester and State of New York, have invented a certain new and useful Improvement in Traffic-Controlling Systems for Railways, of which the following is a specification, reference being had therein to the accompanying drawings, forming part thereof.

My invention relates to improvements in electric traffic-controlling systems for railways, particularly to systems in which traffic-controlling devices carried by a train or vehicles on a railway are responsive to and controlled by electric currentsfrom sources external to the train or vehicle.

One object of my invention is to provide a system of the kind above referred to with novel and simple means for maintaining electrical communication between the stationary parts of the apparatus and the electrically controlled devices carried by the train or vehicle. For this purpose, I utilize, in the present system, the trolley wire, contact rail, or other conductor of traction current, by transmitting through this conductor and through the contact devices carried by the. train or vehicle, a current or currents differing in character from the traction current, While the traffic-controlling devices on the train or vehicle are arranged. and con- 's'tructedto be unaffected by the traction current flowing through the same conductor. More specifically, I use, in the illustrated embodiment of my invention, alternating currents for traction and for controlling the t-rafiic-controlling devices, which are 'difl'erentiated from each other by being of substantially different frequency.

In connection with the traffic-controlling devices carried by the train or vehicle I use, preferably, but not necessarily, stationary traflic-controlling devices, such as track signals, and coordinate to a certain extent, the electric controlling devices by which the stationary traffic-controlling devices and the moving traffic-controlling devices are governed.

Other objects and features of my inven- Specification of Letters Patent.

Patented Dec. 1, 1914.

Serial No. 460,124.

tion, relating more particularly to specific features of construction and operation of the preferred embodiment thereof, will be noted in connection with the description of the illustrated embodiment of the invention.

I will now describe the embodiment of my invention illustrated in the accompanying drawing, and will thereafter point out my invention in claim.

The drawing is a diagram of a portion of an electric traffic-controlling system embodying the present invention, and it represents two complcte blocks, and portions of two adjacent blocks, on the westbound track of a double-track railway, together with a train or vehicle in one of the blocks.

The three signal stations illustrated are designated, respectively, by the letters A, B and C. As the apparatus at the several stations is precisely similar, similar reference numbers are applied to corresponding parts, but in the following description these numbers are followed, where necessary, by the letter A, B or C to indicate the station at which the part in question is located.

The track rails 1 and 2 are bonded, or otherwise rendered continuously conductive, so that they may be utilized as conductors of traction current, and they are also con nected at the ends of the blocks by heavy cross-bonds 3 of negligible impedance.-

A traction-current conductor 4, which may be a trolley wire or a contact rail or any other suitable form of conductor, is'located parallel with the track to furnish trainsthereon with traction -current; This current is fed to the traction circuit at any convenient point by an alternatin :current generator 8, ofwhich one termina isconi nected with the track rails through a. wire 9.

The generator is not connected directly with the traction contact conductor 4, but

the latter is fed at intervals from a feed constitute the secondary windings of transformers 10 by which the currents for controlling the trafic-controlling devices carried by the trains or vehicles are superimposed on the traction current. v The primary windings 11 of the transformers 10 are energized by transformers 12, which are connected with transmission line wires 13, throu 'h which the trans-- formers 12 are supplied with alternating current from a generator 15 connected with the transmission wires through wires 14.

This generator is constructed and voperated i current depends upon the clear condition" of the block in{ advance of such section, and as a convenient means for securing this result the connections between the transformers 12 and the transformers 10 are controlled by track signals which operate automatically under the control of track circuits in the usual manner. Each transformer 12 is connected at its secondary terminals with feed wires 16, and one of the feed wires is con nected through a wire 17 with a primary terminal of the corresponding transformer 10. The other primary terminal of the transformer 10 is'connected by a wire 18 with a fixed contact cooperating with a circuit-breaker 19 connected with the other feed wire, The circuit-breaker is mechanically connected with and actuated by the semaphore track signal 21. The signal is normally in clear position, as shown at B and C, and the circuit-breaker 19 then engages its fixed contact, so that the transformer 10 is energized and energizes the corresponding section of thetraction conductor 4 with traftic-controlling current. When the signal 21 rises to danger position the circuit-breaker 19 is thereby raised so as to break the circuit through the transformer 10 and deenergize thetraction conductor, as far as trailic-controlling current is concerned, in the block to the rear of that controlled by the signal 21. The currents induced in the secondaries 7 flow through the generator 8 so that as regards currents of this frequency the gender-- ator .8 acts merely as a conductor, andthe secondaries? act as conductors for the cur-- rents generated by the generator 8.-

The trailie-controlling devices carried by a train or vehicle and responsive to traffic-.

controlling currents in the traction conductor are illustrated diagrammatically 1n the block A-B. Contact shoes 22 carried by images the train or vehicle engage the traction con ductor 4, and transmit both traction current and trailic-controlling current to the train apparatus through a wire 23. The trafficcontrolling devices are controlled by electric translating means comprismg a relay 24. This relay .is of the polarized alternatingcurrent type, and it has a field which is energized with the alternating trafiic-controlling current from the traction conductor. For this purpose the field is connected through a wire 25 with the wire 23, and through a wire 26 with an axle 27 of the train, so that the relay field is included in the traction-current circuit. In order to prevent any substantial flow of traction current in the relay field a condenser 28 is interposed in the wire 26, this condenser being tuned in resonance with the traffic-controlling current but not with the traction current.

The train relay has an armature 29 which is pivotally mounted in the field and actuates a contact finger 30, cotiperating with a fixed contact 31. The armature is provided with a coil or winding which is constantly energized with current of the same frequency as the traffic-controlling current induced in the transformers 10 and of definite phase relation therewith. F or this purpose the armature coil is connected with a generator same frequency as and of definite phase relation with the trailic-controlling current by which the relay field is energized. Under these circumstances the armature 29 tends to rotate in a direction to maintain its contact finger 30 in engagement with the fixed contact 31. m

The traific controlling devices carried by the train may be of 'various kinds, and I have shown several, including bbth-visual signals and. automatic train-stopping devices. The visual signals coinprise an electric lamp 34 and a min ature semaphore indicator 35. The automatic stopping devices comprise a circuit-breaker 36 by which the i traction motor is thrown. out of operation, and a device for applying the air brakes. The circuit-breaker 36 is normally held closed by a magnet 37 The brake-applying device comprises a magnet 38 controlling an armature 43." The armature is normally raised and it holds closed a valve 44 which controls an escape opening in an air pipe 45 connected with the train pipe of the airbrake system. \Vhen the magnet 88 is de' energized, the valve 4H Opens, the air escapes, and the brakes are applied in the well known manner.

The lamp 3i, indicator 35, magnet 37 and magnet 38 are all connected in series in a circuit controlled by the relay. This circuit is energized, when normally closed, by traction current, and it passes from the wire 23 through a wire 39 to the contact finger 30 of the relay, from the fixed contact 31 through a wire 410 to the traliic-controlling devices, and from the latter through a wire 11 to the Wire 26 and the axle 27. The lamp and the indicator thus normally indicate a clear track ahead, while the stopping devices are inoperative, but it through any cause the traction conductor in the block occupied by the train ceases to be energized with current from the corresponding transformer 10, the field of the train relay is deenergizcd, the armature rotates permitting the contact finger to fall, the lamp 31 is extinguished, the indicator 35 goes to danger position, the circuit-breaker 36 shuts oh? the current from the traction motor 42, and the air brakes are applied.

Since the train is'always, under normal conditions, supplied with traction current, the motor 33, once started, operates indefinitely, and for this reason it need not necessarily be of the self-starting type, but any of the well known self-starting appliances may be used if desired.

It will be obvious that the transformers 10 need not be operated by any particular system of track signals, nor, indeed, by any track signals at all, but I have shown the devices constituting the particular subject matter of my invention as operating in connection with a simple system of home signals arranged in accordance with the invention disclosed in the application of Clyde J. Coleman, filed July 12, 1907, Serial No. 383,366 to which reference is made herein by permission. In this system the track rails and the cross-bonds 3 constitute track circuits in each block. Each track circuit is energized at or near the middle of the block by a transformer 53 of which the secondary terminals are connected, respectively, with the track rails through wires 54. In this arrangement the track circuit, has two branches, and the current flows from the middle of the block through one rail in opposite directions to the ends of the block, then across through the cross-bonds 3 to the other rail, and back therein to the middle of the block.

The track circuits control the signals ductive relation with the track rails near the ends of the blocks. The signal relays 4,8 and 19 are of the same type and construction as the train relay 2 1, and their armature coils are connected with the track coils 46 and =17 respectively. The fields of the signal relays are connected with the feed wires 16 so as to be energized by current from the transformers 12. The contact fingers of the signal relays in each block control a line circuit by whiclr the signals 21 at the entrance to the block is controlled. This circuit is energized by the transformer 12. Referring, for example, to the block B-C, the line circuit passes from the upper feed wire 1(5 through theline wire 50 to the signal 21, thence through a wire 51 to the contact finger and its fixed contact of the signal relay 49, thence through the line wire 52 to the contact finger' and fixed contact of the signal relay 1-8", and thence to the other feed wire 16.

The signal 21 has a bias to danger position, but is provided with electrically controlled mechanism for clearing it. This mechanism may be of any ordinary or suitable form and is not illustrated in the drawings. As the signal relays are normally energized, the line circuits are normally closed, and the signals are held clear by their actuating mechanism, as illustrated at B and C.

When a train or any rolling stock occupies a block, the wheels and axles act to short-circuit one branch or both branches of the track circuit so that one or both of the track. coils and the corresponding relays are dcenergized. The line circuit is thus opened and the signal at the entrance to the block is deenergizcd and goes to danger position. This condition is illustrated in the block AB, where the right-hand branch of the track circuit is short-circuited through the axle 27. The track coil 17* and the armature of the relay 49* are deenergized, and the line circuit through the signal 21 is opened by the relay 19, so that the signal rises to danger position. In so moving the signal actuates the circuit-breaker 19, thereby throwing the transformer 10 out of operation, and thus any train now approaching A will be stopped, not only by the track signal 21 but also by the trafiic-controlling devices carried by the train. I

Various modifications may be made in th embodiment of my invention hereinbefore described and illustrated in the accompanying drawings, within the nature of the invention and the scopeof the following claim.

I claim:

An electric traffic-controlling system comprising a traction circuit, a transformer having its secondary included in the traction circuit, signals along the trackway, a source of alternating current arranged to energize In testimony whereof I have efixed my saidd two]; signalsi and Else the prinlllary signature in presence of two witnesses.

win ing 0 the sai trans ormer, a car aving its traction apparatus included in said ALBERT 5 traction circuit, and traficcontrolling Witnesses:

means on the can responsive to current from HENRY D. WmLLmMs, the said transformer. BERNARD CownN. 

